rx 7800xt - PSU questions.

[charlize]

i plan to get the gigabyte radeon rx 7800xt gaming oc 16g and it's recommended to use a 700W PSU, but i also did read already that some are saying that they run it with a 600 or 650W PSU but without overclocking.

what do you say?

i'm not planning to overclock it!

[Omega]

Get a 750 or better as is recommended by the manufacturer.

In edgecases and with certain PSU units a 650 might not be enough and the PSU may trigger OPP.

[Rumpelcrutchskin]

Recommended to have at least 750W.

[Beaquire]

Psu 650w gold will be enough. Example: XPG core reactor 2 650w gold

[r.linder]

650W is enough if your CPU doesn't draw that much power, for instance a Ryzen 7 7800X3D which can use as little as 50W while gaming would be perfectly fine with a 7800-XT on a quality 650W power supply, the recommendations are usually a worst case scenario with a much more power hungry CPU like a 7950X or 14900K.

The RX 7800-XT only uses around 250W on average while gaming, with 20ms spikes over 300W, there's plenty of room for a 650W unit to handle it fine, it just depends on the rest of the system.

https://www.amd.com/en/products/graphics/desktops/radeon/7000-series/amd-radeon-rx-7800-xt.html#product-specs

"Recommended power supply for AMD Radeon RX 7800 XT graphics card is minimum 700W or greater with 12V output > 54A. Minimum recommended system power supply wattage is based on a PC configured with an AMD Ryzen 9 7950X processor plus typical power requirements of other system components. Your system requirements may differ."

[Rumpelcrutchskin]

Play stupid games with borderline or poor quality PSUs win stupid prizes.

[Tonepoet]

If you have to overspend on any parts in your computer build, it should either be the case or the power supply. The anticipated operational life span of those components is longer than anything else in the computer, and getting a power supply that is more powerful than you need can spare you the trouble of sourcing a second one later down the line. Moreover, if your computer is worth any substantial amount of money, you probably don't want to risk the power supply undergoing catastrophic failure that takes the rest of the system with it. We've basically been using the same standard atx form factor cases for 29 years, and many power supplies are warranted for up to 10 years of use.

Now I understand that meeting budget is often paramount, but if such is the case here you might want to consider buying a 6800 xt instead. It's usually said that the 7800 xt isn't actually much of an upgrade over the 6800 xt, so in the long run you'd be better off paying less on the G.P.U. and more on the P.S.U.

You can save $60 on your graphics card by going with an Asrock Phantom 6800 xt[pcpartpicker.com] and invest that into getting a stronger power supply.

Asrock has a terrible warranty process, but the good news is that they basically have the lowest defect rate among G.P.U. manufacturers in the first place[www.techspot.com], so you very well likely won't need to exercise warranty rights in the first place and it is there as a contingency in case you are one of the unlucky few.

You're probably spending about $60 on a basic power supply in the first place, so by making this change in build plans. you can have a $120 budget for a power supply that would allow you to buy some 850 watt gold rated atx 3.0 power supply like the Corsair RM850e[www.amazon.com], the M.S.I. Mag A850G[www.amazon.com] or the E.V.G.A. Supernova 850g[www.amazon.com].

I wouldn't particularly go E.V.G.A. after they tried to stiff that dude on warranty service after they sent him the P.S.U. with the changed pinouts, but the point is you have choices at this price range.

[Bad 💀 Motha]

A decent brand of 850W Gold/Platinum would be best.

Corsair, ASUS, MSI, BeQuiet

[UserNotFound]

Originally posted by Rumpelcrutchskin:

Play stupid games with borderline or poor quality PSUs win stupid prizes.

Exactly, NEVER scrimp on the PSU, it's literally the heart of the system, and you don't want a bad ticker!!! IF TS wanna stick to a recommended PSU, a 750W one, then get a good quality 750W Gold rated PSU from Corsair, Seasonic, Enermax, Be Quiet!, etc.

My own philosophy is, get something more powerful like a 1000W Platinum PSU for my main rig (5700X3D + RX 7900XTX) and an older (spare) Enermax MAX REVO 1500W PSU for my 2nd rig (R9 5900X + RX 6900XT)

[charlize]

Originally posted by r.linder:

650W is enough if your CPU doesn't draw that much power

idk how much power the r7 3700x consumes.

[Bad 💀 Motha]

A quality 850W is enough for 14th Gen i9 + RTX 4080... Which is alot more power consuming then even Ryzen 7800X3D + 7900 XTX

3700X is around 65W TDP but you have to think about the retest of the system which us about 100W then your GPU. Then you need want to have around 20-25% headroom

[r.linder]

Originally posted by Odessa:

Originally posted by r.linder:

650W is enough if your CPU doesn't draw that much power

idk how much power the r7 3700x consumes.

Up to 88W at stock settings and rarely ever more if PPT is increased, so you're fine.

Total draw between the CPU and GPU wouldn't exceed 450W, worst it would get under power spikes is 400-420W, and for a 650W PSU that leaves more than enough headroom for the rest of the system on the +12V rail.

[Rumpelcrutchskin]

Originally posted by r.linder:

Originally posted by Odessa:

idk how much power the r7 3700x consumes.

Up to 88W at stock settings and rarely ever more if PPT is increased, so you're fine.

Total draw between the CPU and GPU wouldn't exceed 450W, worst it would get under power spikes is 400-420W, and for a 650W PSU that leaves more than enough headroom for the rest of the system on the +12V rail.

Provided it`s actually decent 650W and not some cheap wonder.

[r.linder]

Originally posted by Rumpelcrutchskin:

Originally posted by r.linder:

Up to 88W at stock settings and rarely ever more if PPT is increased, so you're fine.

Total draw between the CPU and GPU wouldn't exceed 450W, worst it would get under power spikes is 400-420W, and for a 650W PSU that leaves more than enough headroom for the rest of the system on the +12V rail.

Provided it`s actually decent 650W and not some cheap wonder.

Already established that it can't be complete crap, AMD's own reqs suggest +12V * 54A or greater which comes down to 648W, as long as the rail can handle it then it's likely to work without any issues.

[Bad 💀 Motha]

CPU TDP + GPU TDP + 100-120 Watts + around 20% overhead

Do not look at CPU makers TDP and go by this alone; look at Wattage output during the heaviest of Benchmarks. For example; those 13th and 14th Gen i9 pushing 250-350 watts just for the CPU. You have to account for this type of scenario, to ensure your never hit the limits of your PSU via your chosen parts. The headroom can be more/less depending on your future needs and also the overall efficiency expected from the chosen PSU.

7800X3D + 7900 XTX = recommend is around 850W Gold/Platinum (750W is too close to borderline and leaves no room for future CPU/GPU that might be more power-hungry.

13th/14th Gen i7/i9 + RTX 4090 (no OC'ing) = around 1000W PSU
^ OC'ing then stay safe and go for 1200W

Gaming PC or Pro Work PC I would not go below 750/850 watts such as Corsair RMX 750 or 850 anyways because the lower models do not tend to have 2x 8pin EPS + 4x 8pin PCIE GPU; which is really what you want to have, in case a future Motherboard and/or GPU requires it.

If you NEED 650 watts for your parts, then get a 850W PSU so you have ample headroom without pushing the PSU too hard under full loads of all your parts.